The present invention relates to hard-surface cleaning compositions especially suited for the cleaning of polished surfaces and methods of using such compositions.
The cleaning of hard surfaces with a variety of compositions is old in the art. The compositions have taken the form of granular solids or liquids while containing such things as scouring and bleaching agents in addition to cleaning surfactant compounds. The interest in providing such compositions, particularly those in liquid form, with antibacterial effectiveness is evidenced by many patents and literature references. Achieving such effectiveness has been the result of using phenolic compounds or quaternary ammonium or other nitrogenous compounds. The presence of such nitrogenous compounds also means that amine impurities are likely to be present. These impurities present a variety of problems, some of which are particularly acute when the compositions are used on polished surfaces.
Many modern floor polishes use carboxyl-containing acrylic copolymers as the basis for detergent and acid resistant, ammonia-removable floor polishes. These copolymers are formed by using a high proportion of acrylic and methacrylic acids, and they are usually cross-linked with a polyvalent metal ion, commonly zirconium or zinc, to form a durable film. This film can be removed with a cleaning solution containing ammonia, the ammonia forming a soluble metal ammoniate complex.
Since the above-mentioned floor polishes are removable by the use of ammonia, the amine impurities which are present in compositions of the instant invention can, through the same chemical interaction, cause the polish to soften and be susceptible to removal. This is undesirable since the polish in such a condition may have a sticky feel and the polished surface will have an unclean, streaky appearance.
It has been found in the present invention that the aforementioned problems can be diminished by the addition of a small amount of a water-soluble metal ion salt to the cleaning composition. It is believed that the metal ion of the salt complexes the amines present thereby preventing them from weakening the cross-linked polish.
It is, therefore, an object of the present invention to provide hard-surface cleaning compositions wherein the tendency of the compositions to soften polishes is substantially reduced.
It is a further object of the present invention to provide a superior method of cleaning polished surfaces.
These and other objects of the present invention will become obvious from the discussion of the invention which appears hereinafter.